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Page 1: A level Physics - Wadebridge School, Cornwall Form/Summer... · 3 Chapter 1 Introduction Welcome to A level Physics at Wadebridge School. We hope you will find this summer project

A level Physics

Summer Project

Name: .

Source: xkcd.com

Page 2: A level Physics - Wadebridge School, Cornwall Form/Summer... · 3 Chapter 1 Introduction Welcome to A level Physics at Wadebridge School. We hope you will find this summer project

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Contents

Chapter Topic

1 Introduction

2 Physical Quantities/Units

3 Standard Form

4 Converting Units to SI Units

5 Prefixes/Converting Unit Magnitudes

6 Re-arranging Equations

7 Using Your Calculator

8 Significant Figures

9 Solving Numerical Problems

If you require any additional help with this project please email

[email protected]

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Chapter 1

Introduction

Welcome to A level Physics at Wadebridge School. We hope you will find this summer project useful

as a primer for starting your advanced studies in September.

One of things that many people find disconcerting when studying Physics is the idea of having to

deal with lots of complicated equations. On first sight, it can be very daunting to see a page full of

letters and symbols but with practice you will see that this is just to save us having to write words

out over and over again (physicists like to work efficiently).

The purpose of this project is to help you develop the core skills needed to solve numerical problems

which will make your Year 12 Physics studies much more enjoyable and successful than they

otherwise would be. Without these core skills solving problems becomes much more difficult if not

impossible, a bit like trying to build a house with no wood or bricks. A bit of work before the course

starts will pay huge dividends later and allow you to work and learn much more efficiently.

In order to give you the best possible chance of success you should complete all the exercises in this

project (on separate lined paper) and bring it with you on the first lesson in September. Within the

first week you will be given a mathematical skills test which will examine your ability to solve more

complex problems using the maths covered in this booklet.

Steps to success

The key to success is to break numerical problems, where calculations are necessary, into smaller,

simpler steps. These steps are the same for all numerical problems and should be followed every

time.

The steps can be summarised as follows:-

Step 1: Write down the values of everything you are given and put a question mark next to what you are asked to work out.

Step 2: Convert all the values into SI units i.e. time in seconds, distances in metres and so on.

Step 3: Pick an equation that contains the values we know and the quantity we are trying to work out.

Step 4: Re-arrange the equation so what we are trying to work out is the subject.

Step 5: Insert the values into the equation including the units.

Step 6: Type it into our calculator to get the answer and quote the answer to a reasonable number of significant figures and with units.

Step 7: Pause for one moment and think about if our answer is sensible.

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With experience some of these steps can be done more quickly or in your head but you should

always show your working. This is for several reasons:-

1. If you don’t show your working, you will needlessly lose many marks in the exam (probably

enough to drop your score by one whole grade, i.e. from B C).

2. It will help make the steps outlined above more apparent and easy to follow when tackling

numerical problems.

3. It makes it easier for the teacher to see where you have gone wrong and therefore help you

learn more quickly and effectively.

Chapter 2:

Physical Quantities/Units

When we first look at numerical problem in Physics we need to be able to recognise what quantities

we are given in the question. This can be made a lot easier if we know what quantity corresponds to

the units given in the question. For example, if a question says someone’s speed changes at a rate of

5 ms-2, you need to be able to recognise that ms-2 is the unit of acceleration and so we know that we

have been given an acceleration (even though the word acceleration wasn’t used in the question).

We can classify physical quantities as either

(a) Basic: These are fundamental which are defined as being independent

There are seven basic quantities defined by the Systeme International d’Unites (SI Units).

They have been defined for convenience not through necessity (force could have been

chosen instead of mass, for instance). Once defined we can make measurements using the

correct unit and measure with direct comparison to that unit.

Basic quantity Unit

Name Symbol

Mass Kilogram kg

Length Metre m

Time Second s

Electric current Ampere A

Temperature Kelvin K

Amount of a substance Mole mol

Luminous intensity Candela cd

NOTE: Base units are also referred to as dimensions. You do not need to learn this table, it is

included for information only.

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(b) Derived: These are obtained by multiplication or division of the basic units without

numerical factors. For example:

Derived quantity Unit

Name Symbols used

Volume Cubic metre m3

Velocity Metre per second ms-1

Density Kilogram per cubic metre kgm-3

Some derived SI units are complicated and are given a simpler name with a unit defined in

terms of the base units.

Farad (F) is given as m-2kg-1s4A2 Watt (W) is given as m2kgs-3

A table of quantities with their units is below along with the most commonly used symbols for both

the quantities and units. (Note that in GCSE we wrote units like metres per second in the format of

m/s but in A-level it is written as ms-1, and this is the standard way units are written at university

level Physics.)

Quantity Quantity

Symbol

SI Unit Unit Symbol

Length L or l Metre m

Distance s Metre m

Height h Metre m

Thickness (of a Wire) d Metre m

Wavelength λ Metre m

Mass m or M kilogram kg

Time t second s

Period T second s

Temperature T Kelvin K

Current I Ampere A

Potential Difference V Volt V

Area A Metres squared m2

Volume V Metres cubed m3

Density ρ Kilograms per metre cubed kg m-3

Force F Newton N

Initial Velocity u Metres per second ms-1

Final Velocity v Metres per second ms-1

Energy E Joule J

Kinetic Energy EK Joule J

Work Done W Joule J

Power P Watt W

Frequency f Hertz Hz

Charge Q Coulomb C

Resistance R Ohm Ω

Resistivity ρ Ohm Metre Ωm

Momentum p kilogram metres per second kg ms-1

Gravitational Field Strength g Newtons per kilogram N kg-1

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This table needs to be memorised – once you know this it will significantly improve your ability to

answer numerical questions. It is so important that we will test you on this very early on in Year

12.

Exercise

For each of the following questions write down the quantities you are trying to work out and write a

question mark next to the quantity you are asked to find out with SI units shown.

You are not expected to actually answer these questions.

Example

1. Find the momentum of a 70 kg ball rolling at 2 ms-1.

𝑀 = 70 𝑘𝑔

𝑣 = 2 𝑚𝑠−1

𝑝 = ? 𝑘𝑔𝑚𝑠−1

1. The resultant force on a body of mass 4.0 kg is 20 N. What is the acceleration of the body?

2. A particle which is moving in a straight line with a velocity of 15 ms-1 accelerates uniformly for 3.0s,

increasing its velocity to 45 ms-1. What distance does it travel whilst accelerating?

3. A car moving at 30 ms-1 is brought to rest with a constant retardation of 3.6 ms-2. How far does it

travel whilst coming to rest?

4. A man of mass 75 kg climbs 300 m in 30 minutes. At what rate is he working?

5. What is the maximum speed at which a car can travel along a level road when its engine is

developing 24kW and there is a resistance to motion of 800 N?

6. Find the current in a circuit when a charge of 40 C passes in 5.0s.

7. What is the resistance of a copper cylinder of length 12 cm and cross-sectional area 0.40 cm2

(Resistivity of copper = 1.7 × 10-8 Ωm)?

8. When a 12 V battery (i.e. a battery of EMF 12 V) is connected across a lamp with a resistance of 6.8

ohms, the potential difference across the lamp is 10.2 V. Find the current through the lamp.

9. Calculate the energy of a photon of wavelength 3.0 × 10-7 m.

10. Calculate the de Broglie wavelength of an electron moving at 3.0 × 106 ms-1 (Planck’s constant = 6.63

× 10-34 Js, mass of electron = 9.1 × 10-31 kg).

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Chapter 3:

Standard Form

You may well already be familiar with Standard Form from GCSE Maths, but just in case you aren’t or

could do with refreshing your memory then this chapter will explain what it is and why we use it.

Why use standard form?

Standard form is used to make very large or very small numbers easier to read. Standard form also

makes it easier to put large or small numbers in order of size.

In Physics, we often deal with quantities that are either really large, such as a parsec

1 pc = 30 900 000 000 000 000 m

Or really small like Planck’s Constant:-

h= 0.000000000000000000000000000000000663 Js

Now, it would be tiresome to write out numbers like this over and over again and so we use a

different notation known as standard form. Standard form shows the magnitude (size) of the

number as powers of ten. We write a number between 1 and 10 and then show it multiplied by a

power of 10.

For example 1.234 x 104

1.234 x 10-4

This means 1.234 x 10 x 10 x 10 x 10 1.234 ÷ 10 ÷ 10 ÷ 10 ÷ 10

Which is 12340 0.0001234

Let’s see some more examples.

0.523 = 5.23 × 10-1 (note that × 10-1 means divide 5.23 by 10)

52.3 = 5.23 × 101 (note that × 101 means multiply 5.23 by 10)

523 = 5.23 × 102 (note that × 102 means multiply 5.23 by 100)

5230 = 5.23 × 103 (note that × 103 means multiply 5.23 by 1000)

0.00523 = 5.23 × 10-3 (note that × 10-3 means divide 5.23 by 1000)

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Note that the sign (positive or negative) in the index tells you whether you are dividing or

multiplying; a positive number means you are multiplying and a negative number means you are

dividing. The number tells you how many times you are either dividing or multiplying by 10. So 1.60

× 10-19 means take the number 1.60 and divide it by 10 nineteen times (divide by 1019). A quick way

to do this in your head is to move the decimal point 19 places to the left.

And to go back to our examples from above:-

1 pc = 30 900 000 000 000 000 m = 3.09 × 1016 m

h = 0.000000000000000000000000000000000663 Js = 6.63 × 10-34 Js

So this is a much shorter way of writing these numbers!

Exercise:

To put a list of large numbers in order is difficult because it takes time to count the number of digits

and hence determine the magnitude of the number.

1. Put these numbers in order of size,

5239824 , 25634897 , 5682147 , 86351473 , 1258964755 , 142586479 , 648523154

But it is easier to order large numbers when they are written in standard form.

2. Put these numbers in order of size,

5.239 x 106

, 2.563 x 107

, 5.682 x 106

, 8.635 x 107

, 1.258 x 109

, 1.425 x 108

, 6.485 x 108

You can see that it is easier to work with large numbers written in standard form. To do this we

must be able to convert from one form into the other.

3. Convert these numbers into normal form.

a) 5.239 x 103

b) 4.543 x 104

c) 9.382 x 102

d) 6.665 x 106

e) 1.951 x 102

f) 1.905 x 105

g) 6.005 x 103

4. Convert these numbers into standard form.

a) 65345 (how many times do you multiply 6.5345 by 10 to get 65345 ?)

b) 28748 c) 548454 d) 486856

e) 70241 f) 65865758 g) 765

Standard form can also be used to write small numbers

e.g. 0.00056 = 5.6 10-4

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5. Convert these numbers into normal form.

a) 8.34 10-3 b) 2.541 10-8 c) 1.01 10-5

d) 8.88 10-1 e) 9 10-2 f) 5.05 10-9

6. Convert these numbers to standard form.

a) 0.000567 b) 0.987 c) 0.0052

d) 0.0000605 e) 0.008 f) 0.0040302

7. Calculate, giving answers in standard form,

a) (3.45 10-5 + 9.5 10-6) 0.0024

b) 2.31 105 3.98 10-3 + 0.0013

Chapter 4:

Converting Units to SI Units

Some common non-SI units that you will encounter during Year 12 Physics:-

Quantity Quantity

Symbol

Alternative Unit Unit Symbol Value in SI Units

Energy E electron volt eV 1.6 × 10-19 J

Charge Q charge on electron e 1.6 × 10-19 C

Mass m atomic mass unit u 1.67 × 10-27 J

Time t hour hr 3600 s

Time T day dy 8.64 x 104 s

Time t year yr 3.16 × 107 s

Distance d light year ly 9.46 × 1015 m

It is essential that you recognise these units and also know how to change them to SI units and

back again. A lot of marks can be lost if you are not absolutely competent doing this.

When you are converting from these units to SI units you need to multiply by the value in the right

hand column. When you convert back the other way you need to divide.

Example

The nearest star (other than the Sun) to Earth is Proxima Centauri at a distance of 4.24 light years.

What is this distance expressed in metres?

4.24 light years = 4.24 × 9.46 × 1015 m = 4.01 × 1016 m

What is this distance expressed in kilometres?

4.01 × 1016 m = 4.01 × 1016 / 1000 km = 4.01 x 1013 km

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Exercise

Convert the following quantities:-

1. What is 13.6 eV expressed in joules?

2. What is a charge of 6e expressed in coulombs?

3. An atom of Lead-208 has a mass of 207.9766521 u, convert this mass into kg.

4. It has been 47 years since England won the World Cup, how long is this in seconds?

5. A TV program lasts 2560 s, how many hours is this?

6. The semi-major axis of Pluto’s orbit around the Sun is 5.91 × 1012 m, what is this distance in

AU?

Converting Speeds

Things get a little more complicated when you have to convert speeds. For example, if Usain Bolt

runs at an average speed of 10.4 ms-1, what is this speed in kilometres per hour?

First, we will change from ms-1 to kms-1:-

10.4 ms-1 = 10.4 / 1000 kms-1 = 1.04 × 10-2 kms-1

Now we have to change from kms-1 to kmhr-1

1.04 × 10-2 kms-1 = 1.04 × 10-2 × 3600 kmhr-1 = 37.44 kmhr-1

Notice that in last line we had to multiply by the number of seconds in an hour. This is because you

would go further in an hour than you would in a second. If you find this hard to understand

sometimes you can multiply by the conversion factor and divide by it and see which value is sensible.

Let’s see what would have happened if we had divided by 3600:-

1.04 × 10-2 kms-1 = 1.04 × 10-2 / 3600 kmhr-1 = 2.89 × 10-6 kmhr-1

Do you think Usain Bolt was running at a speed of about 2 millionths of a kilometre an hour? This is

clearly wrong so we would have realised that we needed to multiply by 3600.

Exercise

1. Convert 0.023 kms-1 into ms-1.

2. Express 3456 mhr-1 into kmhr-1

3. What is 30 kmhr-1 in ms-1?

4. What is 50 ms-1 in km hr-1?

5. Convert 33 kmhr-1 into ms-1.

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Chapter 5:

Prefixes & Converting Unit Magnitudes

How to use and convert prefixes

Often in Physics, quantities are written using prefixes which is an even shorter way of writing

numbers than standard form. For example instead of writing 2.95 × 10-9 m we can write 2.95 nm

where n means nano and is a short way of writing × 10-9. Here is a table that shows all the prefixes

you need to know in Year 12 Physics.

Prefix Symbol Name Multiplier

pico p trillionth 10-12

nano n billionth 10-9

micro µ millionth 10-6

milli m thousandth 10-3

centi c hundredth 10-2

kilo k thousand 103

mega M million 106

giga G billion 109

tera T trillion 1012

Again, it is essential you know all of these to ensure that you don’t lose easy marks when

answering numerical problems. Make sure you spot the difference between the capital and

lowercase letters.

When you are given a variable with a prefix you must convert it into its numerical equivalent in

standard form before you use it in an equation.

Example

Always start by replacing the prefix symbol with its equivalent multiplier.

For example: 0.16 μC = 0.00000016C = 0.16 x 10-6 C

3 km = 3000m = 3 x 103 m

10 ns = 0.00000001 s = 10 x 10-9 s

You might want to avoid taking these further into perfect standard form (for example: 0.16 x 10-6 C

should actually be 1.6 x 10-7 C and also 10 x 10-9 s = 10-8 s) unless you are absolutely confident that

you will do it correctly. It is always safer to stop at the first step (10 x 10-9 s) and type it like this into

your calculator.

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Exercise

1. Convert these into standard form.

a) 1.4 kW = b) 10 μC =

c) 24 cm = d) 340 MW =

e) 46 pF = f) 0.03 mA =

g) 52 Gbytes = h) 43 kΩ =

2. Convert the following: (Remember that milli = 10-3 and centi = 10-2)

a) 5.46 m to cm

b) 65 mm to m

c) 3 cm to m

d) 0.98 m to mm

e) 34 cm to mm

f) 76 mm to cm

Converting between unit magnitudes for areas and volumes

It’s really important that when we convert areas and volumes that we don’t forget to square or cube

the unit.

Let’s take the example of converting a sugar cube of volume 1 cm3 into m3.

If we just use the normal conversion, then 1 cm3 = 1 x 10-2 m3 Wrong Answer!

STOP! Let’s think about this one second:

Imagine in your head a box 1m by 1m by 1m, how many sugar cubes could you fit in there? A lot

more than 100! That would only fill up one line along one of the bottom edges of the box! So our

answer must be wrong.

What we have to do is do the conversion and then cube it, like this:-

1 cm3 = 1 (x 10-2 m)3 = 1 x 10-6 m3.

So this means we could fit a million sugar cubes in the box, which is right.

Exercise

1. What is 5.2 mm3 in m3?

2. What is 24 cm2 in m2?

3. What is 34 m3 in μm3?

4. What is 0.96 x 106 m2 in km2?

5. Convert 34 Mm3 into pm3.

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Chapter 6:

Re-arranging Equations

The first step in learning to manipulate an equation is your ability to see how it is done once and

then repeat the process again and again until it becomes second nature to you.

In order to show the process once I will be using letters rather than physical units.

You can rearrange an equation cba with

b as the subject c

ab

or c as the subject b

ac

Example

Equation First Rearrangement Second Rearrangement

fv

vf

f

v

fT

1

fT 1 Tf

1

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Exercise

From now on the multiplication sign will not be shown, so cba will be simply written as

bca

Equation First Rearrangement Second Rearrangement

(Power of lens) f

P1

1

f

(Magnification of lens) u

vm

v

u

(refractive index) v

cn

c

v

(current) t

QI

(electric potential) Q

EV

(power) t

EP

(power) VIP

(conductance) V

IG

(resistance) I

VR

(resistance) G

R1

(power) RIP 2

(power) R

VP

2

(stress) A

F

F

A

(strain) l

x

x

l

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Exercise

Further rearranging practice questions:

1. a = bc b=?

2. a = b/c b=? c=?

3. a = b – c c=?

4. a = b + c b=?

5. a = bc + d c=?

6. a = b/c – d c=?

7. a = bc/d d=? b=?

8. a = (b + c)/d c=?

9. a = b/c + d/e e=?

Chapter 7

Using Your Calculator

In A Level Physics you will need to use a scientific calculator. We recommend a ‘natural display’

calculator such as the Casio fx-83ES model, shown here:

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Exercise

Using your calculator, evaluate: 30

5 × 3= ?

What answer did you get? 18 or 2? If you got 18 you were wrong. Nope – there’s nothing wrong

with your calculator we just need to establish exactly how it works.

You need to be able to use your calculator confidently to do the following things:

Fractions or decimals

Powers and surds (i.e. square roots)

Making corrections or reusing a previous result

Using your calculator for negative numbers

Using the calculator memory

Using standard form on your calculator

Trigonometry on your calculator

Radians on your calculator

Logarithms, Natural logarithms and powers of e on your calculator

If you are in any doubt about how to the things above on your calculator you should visit the Open

University website and complete their ‘Using a Scientific Calculator’ module here:

http://www.open.edu/openlearn/education/mathematics-education/using-scientific-

calculator/content-section-0

Exercise

Always give your answer in standard form, e.g. 7.0 x 10-3 and not as 7.0-3 or 7000 which is how it may be displayed on the calculator.

Your answer should have the same amount of significant figures as the question.

1. (7.5 × 103) × 24 =

2. (6.2 × 10−5) × (5.0 × 10−3) =

3. (1.4 × 105) × (2.0 × 104) =

4. (4.5×103)

(7.0×104)=

5. 4.3×10−6

6.0×103 =

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Exercise

In each case, find the value of “y”.

1. 𝑦 = (7.5 × 103)2

2. 𝑦 =(1.3×103)× (1.6×10−4)

(6.6×106)+(3.27×10−3)

3. 𝑦 =(5.6×10−4)2×(7.8×108)

(6.6×106)+(3.27×10−3)

4. 𝑦 = √(4.12×103)+(6.5×102)

(2.3×104)×(8.1×102)

Chapter 8

Significant Figures

You can lose a mark if you quote too many significant figures in an answer, it is just as bad as leaving

off a unit when answering a question –why lose marks needlessly when you don’t have to?

The Rules

1. All non-zero digits are significant. E.g. 65290, 5000, 0.34 (numbers highlighted bold are

significant)

2. In a number without a decimal point, only zeros BETWEEN non-zero digits are significant. E.g.

the zeros are significant in 12001 but not in 12100.

3. In a number with a decimal point, all zeros to the right of the right-most non-zero digit are

significant. E.g. 12.100, 2.010, 3.01, 0.0120

Examples

39.389 5 s.f. (5 significant figures)

120000000000000 2 s.f.

3400.000 7 s.f.

34224000 5 s.f.

200000.0004 10 s.f.

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Exercise

How many significant figures are the following numbers quoted to?

1. 224.4343

2. 0.00000000003244654

3. 3442.34

4. 200000

5. 43.0002

6. 24540000

7. 543325

8. 23.5454353

9. 4.0000000000

10. 4456001

For the numbers above that are quoted to more than 3 s.f., convert the number to standard form

and quote to 3 s.f.

Using a Reasonable Number of S.F.

When answering a question you should write your final answer using the same number of s.f. as

those provided in the question. You can sometimes go to just one more.

Example

Let’s say we were faced with this question:

A man runs 110 metres in 13 seconds, calculate his average speed.

Distance = 110 m

Time = 13 s

Speed = Distance/Time = 110 metres / 13 seconds

= 8.461538461538461538461538461538 ms-1

This is a ridiculous number of significant figures!

= 8.46 ms-1 seems acceptable (i.e. given to 3 s.f.) because the figures we were given in the

question we given to 2 s.f. We’ve used just one more than was given in our question which is

fine.

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Exercise

How many significant figures would you quote the answers to the following questions to?

1. The resultant force on a body of mass 4.0 kg is 20 N. What is the acceleration of the body?

2. A particle which is moving in a straight line with a velocity of 15 ms-1 accelerates uniformly for

3.0s, increasing its velocity to 45 ms-1. What distance does it travel whilst accelerating?

3. A car moving at 30 ms-1 is brought to rest with a constant retardation of 3.6 ms-2. How far does

it travel whilst coming to rest?

4. A man of mass 75 kg climbs 300 m in 30 minutes. At what rate is he working?

5. What is the maximum speed at which a car can travel along a level road when its engine is

developing 24kW and there is a resistance to motion of 800 N?

Chapter 9

Example Numerical Problems

A Step by Step Guide on Tackling a Numerical Problem

This example may look lengthy, but that’s because I am describing every step that I do in my head.

Only the yellow shaded bits will end up written down on my paper.

Let’s try a typical question from a worksheet given out in class:

The question says:

Gravitational field strength (g) = 9.81 Nkg-1

2. A book is picked up from the floor by a librarian and placed onto a shelf 2.5 m high. The book has a mass of 500 g. Calculate:

(a) The energy gained by the book.

Step 1: Write down the values of everything you are given and put a question mark next to what you are asked to work out:

g = 9.81 Nkg-1 h = 2.5 m m = 500 g E = ?

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Step 2: Convert all the values into SI units i.e. time in seconds, distances in metres and so on:

From the table on page 11:

1 kg = 103 g

So now replace 500 g with 500/103 kg:

g = 9.81 Nkg-1 h = 2.5 m m = 500 g = 0.5 kg E = ? So our list of known values becomes:

g = 9.81 Nkg-1 h = 2.5 m m = 500 g = 0.5 kg E = ?

Step 3: Pick an equation that contains the values we know and the quantity we are trying to work out:

So we want an equation with m, g, h and E in it. This looks like a job for the gravitational potential energy equation:

𝐸 = 𝑚 × 𝑔 × ℎ

Step 4: Re-arrange the equation so what we are trying to work out is the subject.

We got lucky this time, the thing we are trying work out is the Energy, E, and that is already the subject, so no re-arranging to do!

Step 5: Insert the values into the equation including the units:

𝐸 = 𝑚 × 𝑔 × ℎ = 0.5 𝑘𝑔 × 9.81 𝑁𝑘𝑔−1 × 2.5 𝑚

Step 6: Type it into our calculator to get the answer and quote the answer to a reasonable number of significant figures:

Answer in the calculator:

𝐸 = 12.2625

The value g was quoted to 3 significant figures and the value of h was given to 2 s.f. However the value for m appeared to be only quoted to 1 s.f. but it’s not clear whether this actually was actually to 3 s.f. or if it was indeed rounded to only 1 s.f. In this case quoting our answer to either 2 or 3 significant figures seems reasonable, and both would be given a mark in the exam.

WRITE THIS DOWN

WRITE THIS

DOWN

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𝐸 = 12.2 𝐽 (3 𝑠. 𝑓. )

Make sure you remember to put the unit as well. Energy is measured in Joules (J).

Step 7: Pause for one moment and think about if our answer is sensible. This comes with practice and experience. The first time I tried this calculation out I got an answer of 1.226 × 104 J. I know that a typical car on a motorway has a kinetic energy of around 105 J and it is (hopefully) clear that lifting a book 2.5 m off the floor should require much less energy than that, so clearly I went wrong somewhere. Looking back over my working, I could see that I had accidentally used a value of 500 for the mass, m, instead of the correct value of 0.5 – I had forgotten to convert grams into kilograms in step 2. After a few practice questions, you can do the same and in the exam it is reassuring when you calculate an answer and know that it looks about right.

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General Information

Useful Web Links

These are general links which you may find useful for revision and independent study during the AS

and A2 courses.

http://www.thestudentroom.co.uk/wiki/Physics_Websites

http://www.thestudentroom.co.uk/forumdisplay.php?f=131

http://www.khanacademy.org/#Physics

http://www.s-cool.co.uk/a-level/physics

http://www.physicsclassroom.com/

http://www.school-for-champions.com/physics.htm

http://www.cyberphysics.co.uk/index.html

http://jersey.uoregon.edu/vlab/

Textbooks and revision guides

Within the first couple of days of term you should go to the Library and collect an AS Physics textbook. This book is a detailed guide to the course and it will be yours to look after for the whole of Year 12. The textbook should be brought to every lesson.

Should you wish to purchase a revision guide in addition to the course textbook we will be looking at organising a bulk order at some point in the Autumn term which will normally be at a discount to typical store prices. We do not consider a revision guide a requirement for the course, however, and it will not be needed in lessons.